import asyncio

def callback(sleep_times, loop):
    print("success time {}".format(loop.time()))

def stoploop(loop):
    loop.stop()

if __name__ == '__main__':

    loop = asyncio.get_event_loop()
    now = loop.time()
    loop.call_at(now + 2,callback, 2, loop)
    loop.call_at(now +1,callback, 1, loop)
    loop.call_at(now +3,callback, 3, loop)
    # loop.call_soon(stoploop, loop)
    loop.call_soon(callback, 4, loop)
    loop.run_forever()